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RCitrin
Jan 6, 2008, 03:12 PM
Bah! I got this review sheet in my ninth grade algebra class with equations where we have to solve for x, and I don't remember how to do them.

Here is an example of the kind of problems we are doing:

2x - t = xy + 5

If someone could explain what to do, that would be great thanks!

s_cianci
Jan 6, 2008, 03:23 PM
Get the x by itself on one side of the equation. Treat the y and t as if they were ordinary numbers and do with them what you would do if they were ordinary numbers.

RCitrin
Jan 6, 2008, 03:39 PM
I'm still a little fuzzy... Here's what I've done so far:

2x - t = xy + 5
2x = t + xy + 5
2x - xy = t +5

Now do I divide 2 - y on both sides? I'm not so sure what to do...

cool_dude
Jan 7, 2008, 03:34 PM
OK so this is where you left of
2x - xy = t +5

now you take out the x on the left side so it looks like
x(2-y) = t + 5

now divide by 2-y both sides so you get
x = (t+5)/(2-y)

RCitrin
Jan 7, 2008, 09:05 PM
Ahhh I remember now. Thanks for your help!

cool_dude
Jan 8, 2008, 10:23 AM
Your welcome